package com.ling.filter;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


public class EncodingFilter implements Filter {
	  private String encoding = "utf-8";

	  public void init(FilterConfig filterConfig) throws ServletException {
		  encoding = filterConfig.getInitParameter("encoding"); 
	  }

	  public void doFilter(ServletRequest request,
	                       ServletResponse response,
	                       FilterChain chain)
	      throws IOException, ServletException {
		 
	     HttpServletRequest httpRequest = (HttpServletRequest) request;
	     HttpServletResponse httpResponse = (HttpServletResponse) response;

	     httpRequest.setCharacterEncoding(encoding);
	     httpResponse.setCharacterEncoding(encoding);
	     chain.doFilter(httpRequest, httpResponse);
	  }

	  public void destroy() {
       this.encoding=null;
	  }

}
